Reamer



F. W. HACK.

REAMER.

APPLICATION FILED DEC. 6, 1913.

' v 1,347,740 Patented July 27, 1920.

FRANK w; HACK, or CHICAGO, ILLINOIS.

REAMER.

Specification of Letters Patent. Patented July 2'7, 1920.

Application filed December e, 1918. Serial N 265,539.

To all whom it may concern: i 7

Be it known that I, FRANK W; HACK, a. citizen of the United States of America, and a resident of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Reamers, of which the following is a specification.

This invention relates to the shell type as well as the customary straight or taper shank type of adjustable reamer having central cones for adjusting integral cutting edges, but is applicable to other tools having some ofthe same general characteristics such as hollow boring tools and taps or thread cutting devices.

The objects of the invention are to produce a practicable tool for cutting under or oversize holes without requiring the use of separable blades or arrangements in which it is difficult to uniformly. adjust the cutting edges or in which the desired simplicity and rigidity are lacking.

An illustrative embodiment of this invention is shown in the accompanying drawings, in which- Figure l is a longitudinal sectional view of the reamer.

Fig. 2 is an end view.

Fig. 3 is an end View with the adjusting plugs removed.

Fig. at is a perspective view of a wrench having hexagonal ends of different sizes for respectively engaging the expanding and contracting plugs.

Many forms of adjustable reamers have been designed but are unsatisfactory in many respects, and solid non-adjustable reamers are mainly employed in machine shop work irrespective of the fact that after moderate use there is a measurable variation from the original diameter. The difficulty with many adjustable reamers is mainly that they are ditficult to adjust, lack the necessary rigidity to prevent relative vibration between the cutting edges when working, and are frequently complicated, expensive, or will not fulfil in a single device all of the requirements as to adjust ment for reaming either under or over-size holes. 7

The purposes of the present invention does not require loose blades, adjusting set screws or exterior tapered collars, and is capable of reaming under-size holes for a driving fit, standard holes absolutely to size,

and over-size holes .for a running fit, or

clearance holes.

In the embodiment of the invention shown the exterior design of the reamer follows well known standards having a cylindrical fluted shell or body portion 1 and integral tang or shank 2. The body portion 1 has internal threads 3 and a central cone 4 is formed inside the shell. The end of the shell of largest diameter has a conical seat 5 at its end. This seat and the cone 4: are respectively engaged by the expanding and contracting plugs 6 and 7 which are threaded to fit the internally threaded shell 1. Expansion and contraction of the shell or body portion is made possible by the longitudinal slits on saw cuts 8 extending along the alternate chip spaces 9 between the cutting edges 10. V

The adjusting of the reamer is accomplished by adjusting the thread plugs, one for contracting and the other for expanding the reamer, the adjusting of which is accomplished by a simple double ended wrench shown in Fig. 7. When a size below standard is required the contracting plug 7 is tightened until the required reduction is obtained and the expanding plug 6 is then brought up as far as it will go, looking the reamer positively to that diameter. When a diameter larger than standard isdesired the contracting plug is released and the expanding plug tightened until the desired expansion is obtained, after which the contracting plug is brought up as far as it will go which locks the reamer positively.

For convenience in adjusting, the'plugs 6 and 7 have hexagonal apertures for engagement by wrench 11.

Although but one specific embodiment of this invention has been herein shown anddescribed, it willbe understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim: 1. A tool of the class described, having a hollow cylindrical body portion and a shank or tang at one end of the body portion, said body portion being provided with integral cutting edges, shts extending between. the

cutting edges from the free end of the body portion toward the shank, said body portion being internally threadedat its slotted end, oppositely disposed conical surfaces formed on said body portion, and, a pair of threaded plugs for fitting Within said body portion, said plugs .zizespectively having interior and exterior" conical surfaces engaging the respective conical surfaces on said bodyportion, whereby the turning of said plugs Will effect the expansion and contractionof said tool as desired. c

2. A' tool of theolass described having a hollow cylindr'icalbfody portionand .a shank or tang at one endof the body portion, said body portion being provided with integral cutting edges, slits extending between the cutting edges from the free end of the body portion-toward the shank, said body portion being provided With a conical projection and an oppositely disposed conical seat at its slotted end, and a pair of coacting -complementary conical surfaced members having threaded engagement With said body portion and independently rotatable, Where- I r FRANK W. HACK. 

